Translocation and Metabolism of Carbohydrate Fraction of 14C-photosynthates in ‘French’ Prune, Prunus domestica L.1

Abstract

When 14 CO 2 was administered to leaves on girdled ‘French’ prune spurs, the label was incorporated into sorbitol, sucrose, glucose, fructose, starch, and amylase-insoluble assimilates. The rates of export of soluble sugars and sorbitol and mobilization of starch from leaves were proportional to the rate of fruit growth. The deposition of amylase-inert assimilates in leaves exceeded that of starch, which may account for the gradual increase in specific leaf weight in prunes. The proportion of sorbitol to total sugars in leaf blades and petioles, stem, and peduncle was nearly constant during the 22-day experim ental period but changed abruptly in the fruit. 14 C-sorbitol fed to fruits via their peduncles was metabolized to 14 C-sucrose, but the reverse reaction was barely detectable.